In vitro biological effects of raw and thermally treated asbestos-containing materials

Asbestos cement, the main asbestos-containing material (ACM) manufactured in Italy in the past, is a health hazard whose elimination is a priority concern. Asbestos fibers can be transformed into potentially non-hazardous silicates by high-temperature treatment via complete solid-state transformation. In this study human A549 cells were directly exposed to raw cement asbestos (RCA), chrysotile and cement asbestos subjected to an industrial process at 1200 °C (HT-CA) and raw commercial grey cement (GC) for 24 and 48h, or treated with conditioned culture medium up to 96 h. In our previous studies we demonstrated that the final product of heat treatment of cement asbestos was considerably more inert and had lower cytotoxic potential than the original asbestos material. However, to better evaluate the risks of interactions with the materials, further in vitro investigations were performed concerning fiber-cell superficial interactions, immuno-hystochemical expression of cytochines p53, p53 homologue p73, TNF-related apoptosis- inducing ligand (TRAIL), and conditioned medium effects on cell viability. Data showed more severe cytotoxic damage by raw cement-asbestos compared to the heat treated materials and different expressions of cytochines that exert critical role in regulating the cell response to asbestos-induced DNA damage. These data should be taken in consideration for a safe recycling of thermal transformed asbestos materials

Comparison of germinal center markers CD10, BCL6 and human germinal center-associated lymphoma (HGAL) in follicular lymphomas

<p>Abstract</p> <p>Background</p> <p>Recently, human germinal center-associated lymphoma (HGAL) gene protein has been proposed as an adjunctive follicular marker to CD10 and BCL6.</p> <p>Methods</p> <p>Our aim was to evaluate immunoreactivity for HGAL in 82 cases of follicular lymphomas (FLs) - 67 nodal, 5 cutaneous and 10 transformed - which were all analysed histologically, by immunohistochemistry and PCR.</p> <p>Results</p> <p>Immunostaining for HGAL was more frequently positive (97.6%) than that for BCL6 (92.7%) and CD10 (90.2%) in FLs; the cases negative for bcl6 and/or for CD10 were all positive for HGAL, whereas the two cases negative for HGAL were positive with BCL6; no difference in HGAL immunostaining was found among different malignant subtypes or grades.</p> <p>Conclusions</p> <p>Therefore, HGAL can be used in the immunostaining of FLs as the most sensitive germinal center (GC)-marker; when applied alone, it would half the immunostaining costs, reserving the use of the other two markers only to HGAL-negative cases.</p

In vitro biological effects of raw and thermally treated asbestos-containing materials.

Asbestos cement, the main asbestos-containing material (ACM) manufactured in Italy in the past, is a health hazard whose elimination is a priority concern. As-bestos fibers can be transformed into potentially non-hazardous silicates by high-temperature treatment via complete solid-state transformation. In this study human A549 cells were directly exposed to raw cement asbestos (RCA), chrysotile and cement asbestos subjected to an industrial process at 1200 °C (HT-CA) and raw commercial grey cement (GC) for 24 and 48h, or treated with conditioned culture medium up to 96 h. In our previous studies we demonstrated that the final product of heat treatment of cement asbestos was considerably more inert and had lower cytotoxic potential than the original asbestos material. However, to better evaluate the risks of interactions with the materials, further in vitro investigations were performed concerning fiber-cell superficial interactions, immuno-histochemical expression of cytochines p53, p53 homologue p73, TNF-related apoptosis-inducing ligand (TRAIL), and conditioned medium effects on cell viability. Data showed more severe cytotoxic damage by raw cement-asbestos compared to the heat treated materials and different expressions of cytochines that exert critical role in regulating the cell response to asbestos-induced DNA damage. These data should be taken in consideration for a safe recycling of thermal transformed asbestos materials

Iron topochemistry, surface reactivity and in vitro toxicity of amphibole asbestos

Chemical reactivity of asbestos tremolite from Italy and USA localities and Union Internationale Contre le Cancer (UICC) crocidolite was studied in relation to Fe content, oxidation state, and structural coordination. Direct correlation between amount of Fe 2+ at the exposed M(1) and M(2) sites of the amphibole structure and fiber chemical reactivity was established. The in vitro toxicity of the same samples was investigated on human alveolar A549 cell line. Relationship between crystal-chemical features and cell toxicity is not straightforward. UICC crocidolite has Fe content and chemical reactivity largely higher than that of tremolite samples, but all show comparable in vitro toxic potential. Results obtained evidenced that Fe topochemistry is not a primary factor for induced cell toxicity, though it accounts for asbestos chemical reactivity (and possibly genotoxicity). © 2011 Springer-Verlag

Iron topochemistry and surface reactivity of amphibole asbestos: relations with in vitro toxicity.

Abstract Chemical reactivity of asbestos tremolite from Italy and USA localities and Union Internationale Contre le Cancer (UICC) crocidolite was studied in relation to Fe content, oxidation state, and structural coordination. Direct correlation between amount of Fe2+ at the exposed M(1) and M(2) sites of the amphibole structure and fiber chemical reactivity was established. The in vitro toxicity of the same samples was investigated on human alveolar A549 cell line. Relationship between crystal-chemical features and cell toxicity is not straightforward. UICC crocidolite has Fe content and chemical reactivity largely higher than that of tremolite samples, but all show comparable in vitro toxic potential. Results obtained evidenced that Fe topochemistry is not a primary factor for induced cell toxicity, though it accounts for asbestos chemical reactivity (and possibly genotoxicity)